LI Jianwei1,WU Jianzheng1,2,HU Rijun1,2,ZHU Longhai1,2,ZHANG Likui1 (1 College of Marine Geosciences,Ocean University of China,Qingdao 266100,China;2 The Key Laboratory of Submarine Geosciences and Prospecting Techniques,Ministry of Education,Ocean University of China,Qingdao 266100,China)